arch.

Adjective

archaic (comparative more archaic, superlative most archaic)

1. Of or characterized by antiquity; old-fashioned, quaint, antiquated.
   • A person familiar with the dialect of certain portions of Massachusetts will not fail to recognize, in ordinary discourse, many words now noted in English vocabularies as archaic, the greater part of which were in common use about the time of the King James translation of the Bible. Shakespeare...1848, James Russel Lowell, The Biglow Papers
2. No longer in ordinary use, though still used occasionally to give a sense of antiquity and still likely to be understood by well-educated speakers and are found in historical texts.
   • The language of the Faerie Queene was made archaic Language:— in order to be in keeping with the chivalry of bygone ages that formed its subject.1893, Harrington Hugh Melville Percival, “Introduction”, in The faerie queene: Book 1, page lxi
3. Belonging to the archaic period.

See all 5 meanings of archaic

Adjective

architectural (comparative more architectural, superlative most architectural)

1. Pertaining to architecture.
   • The original family who had begun to build a palace to rival Nonesuch had died out before they had put up little more than the gateway, so that the actual structure which had come down to posterity retained the secret magic of a promise rather than the overpowering splendour of a great...1963, Margery Allingham, chapter 1, in The China Governess: A Mystery, London: Chatto & Windus, →OCLC
2. Resembling architecture in style; seeming to have been designed (by an architect).